/* Stratum AI — Precision Design System */

/* IBM Plex Sans + Mono from Google Fonts */
@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans:wght@400;500;600&family=IBM+Plex+Mono:wght@400;500&display=swap');

/* ── Light theme (default) ── */
:root {
  --paper: #FAFAFA;
  --fog: #F0F2F5;
  --silver: #D8DCE2;
  --graphite: #6B7280;
  --carbon: #374151;
  --midnight: #1A2332;
  --teal: #4DA6A8;
  --teal-deep: #2A7A7C;
  --teal-dark: #3D8B8D;
  --teal-glow: rgba(77, 166, 168, 0.1);
  --amber: #F59E0B;
  --background: #FAFAFA;
  --foreground: #374151;
}

/* ── Dark theme ── */
.dark {
  --paper: #111827;
  --fog: #1A2332;
  --silver: #2D3748;
  --graphite: #9CA3AF;
  --carbon: #D1D5DB;
  --midnight: #F3F4F6;
  --teal: #5CBCBE;
  --teal-deep: #7DD3D5;
  --teal-dark: #4AACAE;
  --teal-glow: rgba(92, 188, 190, 0.1);
  --amber: #FBBF24;
  --background: #111827;
  --foreground: #D1D5DB;
}

/* ── Reset & Base ── */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background-color: var(--paper);
  color: var(--carbon);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  color: inherit;
  text-decoration: none;
}

img, svg {
  display: block;
  max-width: 100%;
}

/* ── Typography ── */
h1, h2, h3, h4 {
  color: var(--midnight);
  font-weight: 600;
  line-height: 1.2;
}

h1 { font-size: 3rem; }
h2 { font-size: 1.875rem; }
h3 { font-size: 1.25rem; }

@media (min-width: 640px) {
  h1 { font-size: 3.5rem; }
}

@media (min-width: 1024px) {
  h1 { font-size: 3.75rem; }
}

.text-teal { color: var(--teal); }
.text-teal-deep { color: var(--teal-deep); }
.text-graphite { color: var(--graphite); }
.text-carbon { color: var(--carbon); }
.text-midnight { color: var(--midnight); }

.font-mono {
  font-family: 'IBM Plex Mono', monospace;
}

/* ── Layout ── */
.container {
  max-width: 72rem;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.container-sm {
  max-width: 48rem;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 3.5rem 1.5rem;
}

.section-fog {
  background-color: var(--fog);
}

.text-center { text-align: center; }

/* ── Buttons ── */
.btn {
  display: inline-block;
  padding: 0.875rem 2rem;
  font-size: 1.125rem;
  font-weight: 500;
  border-radius: 0.5rem;
  transition: background-color 0.15s, border-color 0.15s, color 0.15s;
  cursor: pointer;
  border: none;
  font-family: inherit;
}

.btn-primary {
  background-color: var(--teal);
  color: white;
}

.btn-primary:hover {
  background-color: var(--teal-dark);
}

.btn-outline {
  background: transparent;
  border: 1px solid var(--silver);
  color: var(--carbon);
}

.btn-outline:hover {
  border-color: var(--teal);
  color: var(--teal-deep);
}

/* ── Navbar ── */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 50;
  background-color: var(--paper);
  border-bottom: 1px solid var(--silver);
  transition: transform 0.3s;
}

.navbar.hidden {
  transform: translateY(-100%);
}

.navbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 72rem;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 4rem;
}

.navbar-logo {
  display: flex;
  align-items: center;
  color: var(--midnight);
}

.navbar-logo img {
  height: 2.25rem;
  width: auto;
}

/* Theme-aware logo toggle */
.logo-light { display: block; }
.logo-dark { display: none; }
.dark .logo-light { display: none; }
.dark .logo-dark { display: block; }

.navbar-links {
  display: none;
  align-items: center;
  gap: 2rem;
}

.navbar-links a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--carbon);
  transition: color 0.15s;
}

.navbar-links a:hover {
  color: var(--teal-deep);
}

.navbar-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.navbar-login {
  display: none;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--carbon);
  transition: color 0.15s;
}

.navbar-login:hover {
  color: var(--teal-deep);
}

.navbar-cta {
  display: none;
  padding: 0.5rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 500;
  background-color: var(--teal);
  color: white;
  border-radius: 0.375rem;
  transition: background-color 0.15s;
}

.navbar-cta:hover {
  background-color: var(--teal-dark);
}

/* Theme toggle */
.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--graphite);
  padding: 0.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s;
}

.theme-toggle:hover {
  color: var(--teal);
}

.theme-toggle .icon-sun,
.dark .theme-toggle .icon-moon {
  display: none;
}

.dark .theme-toggle .icon-sun {
  display: block;
}

/* Mobile menu */
.mobile-toggle {
  display: flex;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--carbon);
  padding: 0.25rem;
}

.mobile-menu {
  display: none;
  position: fixed;
  top: 4rem;
  left: 0;
  right: 0;
  background-color: var(--paper);
  border-bottom: 1px solid var(--silver);
  padding: 1rem 1.5rem;
  z-index: 49;
}

.mobile-menu.open {
  display: block;
}

.mobile-menu a {
  display: block;
  padding: 0.75rem 0;
  font-size: 1rem;
  font-weight: 500;
  color: var(--carbon);
  border-bottom: 1px solid var(--fog);
}

.mobile-menu a:last-child {
  border-bottom: none;
}

@media (min-width: 768px) {
  .navbar-links { display: flex; }
  .navbar-login { display: block; }
  .navbar-cta { display: inline-block; }
  .mobile-toggle { display: none; }
}

/* ── Hero ── */
.hero {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 70vh;
  padding: 5rem 1.5rem 3rem;
  text-align: center;
}

.hero-badge {
  display: inline-flex;
  padding: 0.375rem 1rem;
  margin-bottom: 1.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--teal-deep);
  background-color: var(--fog);
  border: 1px solid var(--silver);
  border-radius: 9999px;
}

.hero h1 {
  margin-bottom: 1.5rem;
  max-width: 48rem;
}

.hero-body {
  max-width: 40rem;
  margin: 0 auto 1rem;
  font-size: 1.125rem;
  color: var(--carbon);
}

.hero-tagline {
  margin-bottom: 2.5rem;
  color: var(--graphite);
}

.hero-actions {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

@media (min-width: 640px) {
  .hero-actions {
    flex-direction: row;
    justify-content: center;
  }
}

/* ── Problem Statement ── */
.problem p {
  font-size: 1.125rem;
  color: var(--carbon);
  margin-bottom: 1rem;
}

.problem p:last-child {
  margin-bottom: 0;
}

/* ── Trust Bar ── */
.trust-bar {
  padding: 2rem 1.5rem;
  background-color: var(--fog);
}

.trust-label {
  text-align: center;
  font-size: 0.75rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--graphite);
  margin-bottom: 1.5rem;
}

.trust-items {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 2rem;
}

.trust-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: var(--carbon);
}

.trust-item svg {
  color: var(--teal);
}

.trust-item span {
  font-size: 0.875rem;
  font-weight: 500;
}

.trust-disclaimer {
  margin-top: 1.5rem;
  text-align: center;
  font-size: 0.75rem;
  color: var(--graphite);
  max-width: 48rem;
  margin-left: auto;
  margin-right: auto;
}

.trust-disclaimer a {
  text-decoration: underline;
}

.trust-disclaimer a:hover {
  color: var(--teal-deep);
}

@media (min-width: 768px) {
  .trust-items { gap: 3.5rem; }
}

/* ── Feature Cards ── */
.card-grid {
  display: grid;
  gap: 1.5rem;
}

.card-grid-3 {
  grid-template-columns: 1fr;
}

.card-grid-2 {
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .card-grid-2 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 768px) {
  .card-grid-3 { grid-template-columns: repeat(3, 1fr); }
}

.card {
  padding: 2rem;
  border-radius: 0.75rem;
  border: 1px solid var(--silver);
  background-color: var(--fog);
  transition: border-color 0.15s;
}

.card:hover {
  border-color: rgba(77, 166, 168, 0.4);
}

.card-icon {
  display: inline-flex;
  padding: 0.625rem;
  margin-bottom: 1rem;
  border-radius: 0.5rem;
  background-color: var(--teal-glow);
  color: var(--teal);
}

.card h3 {
  margin-bottom: 0.25rem;
}

.card-subtitle {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--teal-deep);
  margin-bottom: 0.75rem;
}

.card p {
  color: var(--carbon);
}

/* ── How It Works ── */
.steps {
  display: grid;
  gap: 2rem;
}

@media (min-width: 768px) {
  .steps { grid-template-columns: repeat(3, 1fr); }
}

.step {
  text-align: center;
  padding: 2rem;
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 3rem;
  height: 3rem;
  margin-bottom: 1rem;
  border-radius: 9999px;
  background-color: var(--teal-glow);
  color: var(--teal);
  font-size: 1.25rem;
  font-weight: 600;
}

.step p {
  color: var(--carbon);
  font-size: 0.875rem;
}

/* ── Security Section ── */
.security-card {
  display: flex;
  gap: 1rem;
  padding: 1.5rem;
  border-radius: 0.75rem;
  border: 1px solid var(--silver);
  background-color: var(--paper);
}

.security-icon {
  flex-shrink: 0;
  color: var(--teal);
}

.security-card h3 {
  margin-bottom: 0.25rem;
}

.security-card p {
  font-size: 0.875rem;
  color: var(--carbon);
}

.security-note {
  margin-top: 2rem;
  text-align: center;
  font-size: 0.875rem;
  color: var(--graphite);
}

/* ── Footer ── */
.footer {
  border-top: 1px solid var(--silver);
  padding: 2.5rem 1.5rem;
  background-color: var(--fog);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  max-width: 72rem;
  margin: 0 auto;
}

.footer-logo img {
  height: 1.75rem;
  width: auto;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer-links a {
  font-size: 0.875rem;
  color: var(--graphite);
  transition: color 0.15s;
}

.footer-links a:hover {
  color: var(--teal-deep);
}

.footer-bottom {
  border-top: 1px solid var(--silver);
  padding-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-copyright {
  font-size: 0.75rem;
  color: var(--graphite);
}

.footer-email a {
  font-size: 0.75rem;
  color: var(--graphite);
  transition: color 0.15s;
}

.footer-email a:hover {
  color: var(--teal-deep);
}

@media (min-width: 768px) {
  .footer-inner {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

/* ── Pricing Page ── */
.pricing-hero {
  padding: 6rem 1.5rem 2rem;
  text-align: center;
}

.pricing-hero h1 {
  margin-bottom: 1rem;
}

.pricing-hero p {
  font-size: 1.125rem;
  color: var(--carbon);
  max-width: 32rem;
  margin: 0 auto;
}

.price {
  font-size: 2.25rem;
  font-weight: 600;
  color: var(--midnight);
}

.price-unit {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--graphite);
}

.feature-list {
  list-style: none;
  padding: 0;
}

.feature-list li {
  padding: 0.5rem 0;
  font-size: 0.875rem;
  color: var(--carbon);
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.feature-list li::before {
  content: "✓";
  color: var(--teal);
  font-weight: 600;
  flex-shrink: 0;
}

/* ── Contact Form ── */
.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  margin-bottom: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--midnight);
}

.form-input,
.form-textarea {
  width: 100%;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  font-family: inherit;
  color: var(--carbon);
  background-color: var(--paper);
  border: 1px solid var(--silver);
  border-radius: 0.5rem;
  transition: border-color 0.15s;
}

.form-input:focus,
.form-textarea:focus {
  outline: none;
  border-color: var(--teal);
}

.form-textarea {
  min-height: 8rem;
  resize: vertical;
}

/* ── Utilities ── */
.mb-4 { margin-bottom: 1rem; }
.mb-6 { margin-bottom: 1.5rem; }
.mb-8 { margin-bottom: 2rem; }
.mb-16 { margin-bottom: 2.5rem; }
.mt-6 { margin-top: 1.5rem; }
.max-w-2xl { max-width: 42rem; margin-left: auto; margin-right: auto; }

/* Beta release chip — paired with product wordmark.
 * Byte-identical to the rule in /public/theme.css; GA toggle flips both.
 * See docs/decisions/0052-beta-tagging-and-ga-toggle.md
 */
.beta-chip {
    display: inline-flex;
    align-items: center;
    margin-left: 0.5rem;
    padding: 2px 7px;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: #2A7A7C;
    background-color: rgba(77, 166, 168, 0.15);
    vertical-align: middle;
    line-height: 1.2;
}
.dark .beta-chip {
    color: #5CBCBE;
    background-color: rgba(92, 188, 190, 0.18);
}

/* Pricing — strikethrough GA price above active beta price */
.price-ga {
    font-size: 0.95rem;
    font-weight: 400;
    color: var(--graphite);
    text-decoration: line-through;
    margin-bottom: 0.125rem;
}
.price-helper {
    font-size: 0.8rem;
    color: var(--carbon);
    margin-bottom: 1rem;
}

/* "In Development" pill — non-purchasable product status. Distinct from .beta-chip
 * (which signals an active beta product). Pale-fog background, graphite text.
 */
.status-pill {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--graphite);
    background-color: var(--fog);
}